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Contribution deals with the problem of insulating system's condition diagnosing with aim to upgrade the level of its real state ranking. After the description of diagnosing methodology used real on-site acquired data are presented. Main accent is at monitoring of discharge activities. This method is perhaps the only, which enables to detect smaller anomalies in high-voltage insulation systems as well...
In this paper, accelerated aging process on induction motor insulation caused by high humidity environtment is investigated. Induction motor is operated inside experiment chamber with high humidity to accelerate the insulation deterioraton. Insulation resistance (IR) and polarization index (PI) values are used to evaluate insulation condition. Moreover Scanning Electron Microscopy-Energy Dispersive...
Resistive switching memory (RRAM) devices are gaining momentum as next generation memory technology for high density and embedded storage. To support technology development by the industry, the scaling and reliability of 1 kb RRAM must be understood and predicted. This work addresses data retention of resistance states in RRAM arrays based on HfO2. We develop a new method for studying retention statistics...
A highly accelerated test method was developed that can stress copper vias on a wafer to 100% failure in just a few minutes. Other test methods like constant current, constant voltage and isothermal tests can take many hours to reach even 50% failure. Most of these test methods require packaging, special test boards and ovens. Unlike constant stress methods our method uses a current “staircase” ramp...
In a raised floor data center, cold air from a pressurized sub-floor plenum reaches the data center room space through perforated floor tiles. Presently, commercially available tool "Flow Hood" (also known as "Balometer") is used to measure the air flow rate through the tiles. In the present paper, we will discuss the operating principle and the shortcomings of the commercial tool...
An improved sensitivity enhancement technique for strain and temperature measurement has been presented. In the present work, the conventional Wheatstone's bridge has been modified using active devices for enhancement of sensitivity by twelve times. It can also measure incremental resistance precisely and linearly. Experiments have been carried out for validation of the proposed circuit for both strain...
IEEE 1451 standard defines an interface for connecting transducers to microprocessor based data acquisition systems, instrumentation systems, control and field networks. A Smart Transducer Interface Module (STIM) is a unit which provides signal conditioning, digitization and data packet generation functions to the transducers connected to it. This paper describes the implementation of a microcontroller...
This paper reports an inside-encapsulation ovenization method for the temperature compensation of Lamé-mode epi-sealed silicon resonators. With this method, the square Lamé-mode resonator itself acts both as a thermometer and a heater, which allows for simultaneous in situ sensing and control of the operating temperature. In this device, only the resonating element is heated, reducing the power consumption...
Recent advancement in solid state technology has made LED lighting energy-efficient and today it is one of the rapidly-developing lighting technologies. Design of LED lighting luminaires is still repeatedly governed by misinterpretations and inappropriate use of the related solid state lighting technology. Heat is generated as byproduct of the light generation process at the LED junction; this heat...
The influence of gas penetration on the lifetime of an ultra-thin polymer pulsating heat pipe (PPHP) was studied experimentally using two types of PPHPs. One type was made with bare polyethylene terephthalate (PET) films and was 0.4 mm thick. The other was covered by gas-barrier films and was 0.48 mm thick. First we compared the performance degradation of the PPHPs made with bare PET films exposed...
Taking into account the real working temperatures from different zones and daily requirement of reduction of production costs, into automotive electronics production the trend is the one towards low melting point alloys that will enable energy savings and cost reductions during the manufacturing processes. In the paper, the mechanical strength of solder joints and samples having the same transversal...
We report on a complete roll-to-roll (R2R) processed rigid-to-flex interposer using poly(3,4-ethylenedioxythiophene) : poly(styrenesulfonate) (PEDOT:PSS) doped with ethylene glycol (EG), spray coated onto a plastic polyethylene naphtalate (PEN) substrate with another single-sided adhesive PEN foil acting as a contact stencil mask for the interposer structures. A 355 nm solidstate R2R integrated laser,...
Body temperature is one of vital signs which can reflect physical status of an individual. Digital thermometers are adopted in clinical gradually in recent years. But few thermometers are really used in clinical because the measurement accuracy or measuring time. In the paper, we designed an improved digital thermometer which has both fast response and high precision. For excellent performance, 1)...
This paper presents two methods for the efficiency measurement of a white light emitting diode (LED) without optical sensors for measuring light intensity. The proposed methods are based on the measurement of the power loss of a white LED. Because all the power loss of a white LED is transferred into heat, it is possible to evaluate the power loss by measuring the temperature of the heat sink attached...
The power consumption of portable devices such as smartphones and notebook PCs has been increasing in recent years as the performance of these devices has advanced. Consequently, a power supply with a higher energy density is required. Direct methanol fuel cells (DMFCs) have a theoretical energy density that is ten or more times greater than that of the current lithium ion batteries, which makes them...
High-voltage switchgear requires sliding and plug-in connections with rated continuous currents up to several kiloamperes and rated short-time withstand currents in the range of tens of kiloamperes. In these high power connections, spring loaded contact elements realize the electric and thermal contact of plug and socket. Contact elements transfer the total electric current of the main circuit and,...
The characteristics of commercially available silicon carbide power devices and packaging technologies have been measured up to 350°C in order to obtain their reliability and suitability for use in a hybrid electric vehicle application. Electro-thermal simulations of representative power module packaging structures, using measured conduction losses, revealed the respective temperature profiles of...
The paper discusses thermal transient measurements of advanced devices which operate in a temperature range where linearity cannot be assumed. However, finding a proper physical equation; valid on a wide temperature range for a device category; their calibration can be carried out at convenient temperatures. The validity of the technique can be verified by good fit of calibrated transients at different...
Solid State Lighting technologies are becoming more and more attractive in the lighting market. Thermal management is a key issue, which impacts efficiency but also colour stability and reliability of LED-based systems. In this paper, we describe and discuss such issues through various examples of different projects by analysing both the heat transfer mechanisms and their impact on the choice of materials...
This work deals with the designing of an oscillator based bridge set-up that can be used for in-circuit resistance measurement for a wide range of values. The circuit utilizes op-amp based active bridge in integration with relaxation oscillator to convert the resistance change into time period or duty cycle. The addition of an oscillator makes the bridge self-sustaining in nature. A novel, low cost,...
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